In Casey Simpson's Living History episode on John Locke, the focus is on Locke's role as a pivotal Enlightenment thinker and the "father of liberalism." The episode explores his ideas of the social contract, natural rights to life, liberty, and property, and the concept of government by consent, which influenced the U.S. Declaration of Independence. It highlights Locke's empiricism, particularly his "tabula rasa" theory, emphasizing knowledge gained through experience. The episode also touches on his advocacy for religious toleration and separation of powers, shaping modern democratic principles.